Sectional grating



Feb.t2`, v1946. g H. NAGIN N L ,2,394,713 w sEcfrIoNAL GRATI'NG l Filed Sept.` l5, 1941 2 Sheets-Sheet 1 Patented Feb. 12, 1946 Umrfr-:D STATES PATENT y OFFICE SECTIONAL GRATING Application September 15, 1941, Serial No. 410,941

Claims.

This invention relates to sectional grating, and particularly to grating which is made of structural units which can be expeditiously jo-ined to adjacent units when laid in place, and can be readily removed from such position should it prove desirable to do so. The invention resides in the particular unit itself, in the assembly of the units, and also in the means for joining adjacent units firmly together in such manner that a unit can be readily detached from the adjoining units and removed and the same or another .unit put in place of the unit removed.

In some instances it is desirable to cover an area with grating, the area being too large to be covered by a grating made in one piece. Itis the custom to make the necessary area of grating in units or sections, each unit being Iof a size which can be readily and economically fabricated in a shop and then transported to the site to be covered. When placed in final position the grating may rest on suitable spaced-apart supports, or it may rest on the ground or other continuous surface. It is sometimes necessary that a portion of the grating covering the area be removed either to gain access to a surface or to a space below thevarea, or a portion of the grating may be damaged and have to be replaced. This requires that the units be joined in such manner that any unit or any number of units be readily removable from its position in the grating area and readily replaceable, and that the runits be interchangeable. Difhculty has been encountered in this respect as it must be borne in mind that the means employed lfor fastening the units together shall provide a strong and rigid joint, be secured to the unit itself without causing appreciable diminution in the strength of the unit, and a joint that can be expeditiously secured or unfastened by unskilled vhelp andI sometimes under extremely adverse conditions. It is also advantageous on occasions to space -each unit apart from the adjoining units. These requirements are all met in my invention.

In the drawings wherein I have shown for purposes of illustration only the present preferred embodiment of my invention:

Figure l is a plan view of a grating unit;

Figure 2 is a sectional view along the line lI-II of Figure 1; Y

Figure 3 is a view, on a larger scale than Figure 1, showing a junction area where portions of three units are joined together;

Figure 4 is a view in elevation along the line IV-IV of Figure 3;

Figure 5 is a sectional View along the line V-V of Figure 4;

Figure 6 is a plan view of a wing bar; Figure 7 is a view in elevation of the wing bar 5 shown in Figure 6;

Figure 8 is a diagrammatic plan view showing the units in position covering an area;

Figure 9 is a plan View of another form of wing bar;

Figure 10 is a plan View of still another form of wing bar; and

Figure 1l is a detail of a portion of a unit slightly different from that shown in Figure 1.

In the drawings, Figures 1 through 7, there is l5 shown a section or unit A of grating which is made from spaced-apart rectangular metal bearer bars 2 which run on edge substantially' parallel to each other, and longitudinally of the unit and for the length thereof. The outside bearer bars are referred to as side bars and designated by the numeral 3. At suitable intervals vthe bearer bars are joined by the metal cross-bars 4 which are arranged at substantially .right angles to the bearer bars and are joined thereto in any suitable manner, such as by welding, and usually by electric pressure resistance welding. Usually, but not always, the tops of all the bars are in a common plane. The bottoms of the longitudinal bearer bars are joined by stieners 5 which are metal bars secured as by electric pressure resistance welding to the bearer bars, and extend substantially at right angles thereto. The stieners extend' the full width of the unit and are more widely spaced apart than are the cross-Ibars. In certain light weight units the stiffeners can be dispensed with. At each end of the unit, end bars 6 are provided. They are substantially the same depth as the bearer .bars 2 and are welded to the ends thereof. 40 The side bars 3 and the end bars 6 are welded together to form a continuous outside member or frame.

Attached to the outside member at predetermined intervals are connector members or wing bars 'I of crenelated shape formed from metal bars of approximately the same'y depth as the bars forming the outside members. The wing bar 1, which is shaped as shown in Figures 6 and 7, has two spaced-apart and outwardly directed 50 U-portions 8 and 9 intermediate the contact portions Ill and I I. This provides two land portions I2 and I3 on one side, and three contact portions I0, I I and I4 on the other side and which lie in a common plane. The extreme ends of the portions I0 and I I are tapered as shown. The lands lie ad- Vjoining the ends of the longitudinal bars.

jacent the outside member of one unit and the portions lie nat against the outside member of an `adjacent unit. Each wing is secured to the out- Vside member by rivets l which pass through the `lands I2 and i3 and through the side bars and fend bars forming the outside member or it may be secured in any other convenient manner, asY

by welding. The wings are secured to the end portions inrstaggered relation, so that when a unit is turned end for end the wings are in the same relative positions, and when two units areV `butted the wing bars from the end of one unit will lie between the wing bars in the abutting end of the other unit. The lands and contact portion are spaced apart a'distance equal to theV 1 placement of any unit, said means including a desired space between adjacent units. This provides automatic and accurate spacing of the Vthe end portions oi the Wing bar adjacent the :clip are bent outwardly and away from the outside memberas shown in dotted lines and desig-v nated Ia in Figure 3,

Thevunits are placed over the support in staggered relation to each other as shown diagram- K matically in Figure 8. The plan view of the assembled units resembles the elevation of an ordinary brick wall in which the end joints are broken but the longitudinal joints are not. If dejsired, however, the longitudinal joints could be broken instead of the end joints, in which case `the end joint would be continuous. If this arrangement Was adopted the wing bars on the `longitudinal side of the bars would have to be staggered to cooperative position. f

It Will be observed that the wing bars have two lands on one side and three contact portions on the other. ThisV makes a very strong type of fastening devicewhich has no tendency to bend or get out of line. The wing` bars can be made heavier thanthe outermembers and thus form a stronger connection without materially increasing the weight of the unit. Instead of having the wing bars crenelated the bar 'la can be serpentine in form with the end portions nat as shown in Figure 9. The wing bar VIl shown in Figure has one U-shaped portion I8 and two outwardly directed contactportions I9 and 2 0. The land or bottom 2| of the portion i3 is riveted to the outer member by rivets 22. Y v

In Figure l1 there is shown a unit which in- Y stead'of being formed of longitudinal bars and transverse cross-bars is formed from an outside member or frame comprisingktwo longitudinal spaced-apart side bars 23, and two endbars 24 The intermediate bearer bars and cross-bars of the `structure shown in Figure lare replaced in this vfastening vthe units together to cover an area are the same as that hereinbefore described.

I WhileIhave described certain preferred ern- V75 bodiments of my invention, it will be understood tending across the unit, end bars crenelated Wing bar secured to the frame member of one unit, each bar having a land which is rigidly'fastened to the frame of one unit, Vand `contact portions spaced from the land portion,

and band clips slidably mounted on the frame member for engaging the contact portions of wing bars fastened to an adjoining unit.

' 2.' For use in a section grating composed of like separable units detachably joined together, said separable units each comprising spaced apart longitudinal bearer bara-transverse cross bars secured to the tops of the bearer bars and eX- tending across the unit, end bars extending the Width of the unit and secured to the ends of the longitudinal bars, the outer bearer bars and end bars being joined to form an outside member, means for connecting said units in a manner permitting ready attachment of and removal of a unit, said means including crenelated wing bars secured to adjacent outside members at co-operating locations to permit staggering of joints, each of said crenelated bars having contact portions extending in the direction of portions of the outside member to which it is attached and spaced from Vthe outside member, and band clips for slidably engaging the contact portion of a wing bar and embracing the outside member of an adjoining unit. Y Y

3. For use in a section grating composed of like separable un'its detachably joined together, said separable units each comprising spaced apart longitudinal bearer bars, transverse cross bars.

secured to the tops of the bearer 'bars and exextending the width of the .unit and secured to the ends yofthe longitudinal bars, the outer bearer bars and end bars being'joined to form a continue ous frame member, means Yfor connecting'said units in a manner permitting ready attachment i of and removal of a unit, said means including serpentine wing bars secured to adjacent frame members at co-operating locations to permit contact portion of'a wingfbar and the frame member of an adjoining unit. Y

4. A structural unit to be joined to a plurality of similar units to form a sectional grating, said unit comprising a rectangular grating having side bars and end bars, connector members secured to the side and end bars, each of said connector membersbeing integrally formed and havingat y least two land portions which contact the bar Y to which the connector member is secured and at least three contact portions for engaging a bar of a similar adjacent unit, theside bars and end bars having slidable clips thereon anchored against transverse separation therefrom and located intermediate theA connector members which engage certain of the contactportions of the connector members of adjacent units.y

5. A structural unit to be joined to a plurality of similar units to form a sectional grating, said unit comprising a rectangular grating having side bars and end bars, connector members secured to the side and end bars, each of said connector 5 members being integrally formed and having at least two land portions in a common plane which contact the bar to which the connector member is secured and at least three contact portions in 

